Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 20, 22

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- Definition

The effective interest rate at the end of the reporting period.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-SubTopic 210

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-Subparagraph (SX 210.5-02.22)

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20, 22

-Article 5

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Credit Arrangements (Narrative) (Details) - USD ($)			9 Months Ended	12 Months Ended
Credit Arrangements (Narrative) (Details) - USD ($)	Feb. 18, 2015	Aug. 22, 2014	May. 31, 2015	Aug. 31, 2006	Feb. 19, 2015	May. 31, 2014
Debt Instrument [Line Items]
Long-term debt outstanding			$ 117,404,000
Series 2006A Bonds [Member]
Debt Instrument [Line Items]
Maturity date			Sep. 01, 2026
Long-term debt outstanding			$ 2,404,000
Five Year United States Treasury Notes [Member] \| Series 2006A Bonds [Member]
Debt Instrument [Line Items]
Basis spread				0.45%
Interest rate			1.94%
Senior Notes [Member]
Debt Instrument [Line Items]
Debt face amount					$ 115,000,000
Debt instrument, stated interest rate					3.82%
Maturity date			Feb. 19, 2030
Effective date			Feb. 19, 2015
Long-term debt outstanding			$ 115,000,000
Amended Credit Facility [Member]
Debt Instrument [Line Items]
Unsecured line of credit, maximum borrowing capacity	$ 50,000,000
Line of credit, amount outstanding			0			$ 0
Available borrowing amount			$ 44,000,000
Interest rate			1.08%
Commitment fee percentage	0.25%
Amended Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Basis spread	0.90%
Rabobank Credit Facility [Member]
Debt Instrument [Line Items]
Unsecured line of credit, maximum borrowing capacity		$ 5,000,000
Line of credit, amount outstanding			$ 0
Interest rate			1.33%
Basis spread		1.15%
Commitment fee percentage			0.25%
Standby Letters of Credit [Member]
Debt Instrument [Line Items]
Line of credit, amount outstanding			$ 6,000,000